Berlin 2015 – scientific programme

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HL: Fachverband Halbleiterphysik

HL 98: Nitrides: Bulk material, films, surfaces and quantum wells

HL 98.9: Talk

Friday, March 20, 2015, 11:45–12:00, EW 201

Optical investigations of anisotropic strain of nonpolar GaInN quantum wells grown on AlInN/GaN buffer layers — •Fedor Alexej Ketzer, Ernst Ronald Buss, Philipp Horenburg, Holger Jönen, Heiko Bremers, Torsten Langer, Uwe Rossow, and Andreas Hangleiter — Institut für Angewandte Physik, Technische Universität Braunschweig

We investigate the effect of different buffer layers on the anisotropic strain of nonpolar GaInN quantum well (QW) structures. Therefore we examine optical properties of QWs grown via low pressure MOVPE. We compare fully strained QWs grown on m-plane pseudobulk GaN substrates with similar samples with AlInN buffer layers of different composition. The effect of the strain of the active zone is investigated by temperature dependent and polarization resolved resonant photoluminescence spectroscopy. Since high strain is prominent in GaN/GaInN heterostructures, AlInN buffer layers provide a good possibility of changing overall strain and relaxation. Due to the deformation potentials which strongly affect the band energies, changing the indium content and relaxation of the buffer layer can further tune the emission wavelength and the degree of polarization of the emitted light. Our samples show good optical properties with narrow spectra but strong differences in the degree of polarization and transition energy compared to samples with regular GaN buffer. This is in good agreement with our calculations of the strain and valence band energies.